The 74th Special Name-list of Variable Stars
We present the Name-list introducing GCVS names for 3153 variable starsdiscovered by the Hipparcos mission.
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Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
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Spectral types of 80 early-type stars of variable radial velocity
MK spectral types are given for 80 normal early-type stars of variableradial velocity. These spectral types were determined from spectrogramstaken with the Lick Observatory 0.9-m refractor during the years1957-58.
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The period distribution of unevolved close binary systems
Period distributions have been examined for various spectral types ofabout 600 (eclipsing and spectroscopic) close binaries, which are likelyto be substantially unevolved. The comparison with the previouscorresponding analyses of extensive (but heterogeneous) binary samplesallows a clarification of the extent of the evolutionary andobservational selection effects. Remarkably, this analysis reveals agreat deficiency of short period binaries (with periods corresponding tocase A mass transfer) in the whole spectral range. For the late spectraltypes, this result may be connected with postformation angular momentumloss caused by stellar wind magnetic braking; at least for the late Band A spectral range, a ready interpretation of this finding is thatclose binaries of corresponding periods and spectral types are rarelyformed.
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A search for X-ray binary stars in their quiescent phase
Fourteen early-type stars representative of systems which may beharboring a neutron star companion and are thus potential progenitors ofmassive X-ray binaries have been examined for X-ray emission with theHEAO A-1 experiment. Limits on the 0.5-20 keV luminosity for theseobjects lie in the range 10 to the 31-33 erg/sec. In several cases, thehypothesis of a collapsed companion, in combination with the X-raylimit, places a serious constraint on the mass-loss rate of the primarystar. In one instance, an X-ray source was discovered coincident with acandidate star, although the luminosity of 5 x 10 to the 31 isconsistent with that expected from a single star of the same spectraltype. The prospects for directly observing the quiescent phase of abinary X-ray source with the Einstein Observatory are discussed in thecontext of these results.
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Detection of low eccentricity orbits - an analysis of nine massive spectroscopic binaries
The elements of nine single-lined, short-period, massive spectroscopicbinaries are analyzed for significant orbital eccentricity. The Fouriertransform formalism for computation of orbits is used to derive anestimator of significance for the observed eccentricity. Of the ninesystems investigated, five are either probably or possibly in eccentricorbits.
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Seventh catalogue of the orbital elements of spectroscopic binary systems.
Not Available
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Duplicity of late B-type stars
High-dispersion spectroscopic observations of 83 stars are used todetermine the binary characteristics of late B-type stars. For a randomsample of such objects, including peculiar as well as normal stars, thefrequency of binaries with mass ratios m2/m sub 1 greaterthan 0.1 and orbital periods less than 100 days is estimated to be about24%, and the frequency of binaries decreases with decreasingm2/m sub 1. In both respects, the late B-type stars aresimilar to early B-, late A-, and solar-type stars. For the majority ofstars with an orbital period greater than 4 days, the observedrotational velocity exceeds the value that corresponds to synchronism ofrotation and revolution, but the ratio of the observed to thesynchronous rotational velocity seldom exceeds a factor of 2 even forperiods as long as 15 days. An additional 20% of the stars surveyedexhibit low amplitude-velocity variations that, if due to orbitalmotion, correspond to m2 m1 less than 0.1. Themost likely explanation is that these systems are close binary remnantsthat have already passed through the mass-transfer phase, with thepresent secondary being a white dwarf.
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A search for optical pulsations from single line spectroscopic binaries.
Summary. Electron collision cross-sections and radiative transitionprobabilities are presented for Si+ 3, +5, Ca + and Fe +15 of the sodiumisoelectronic sequence. An attempt is made to interpret the observedrelative intensities of Si Iv and S vI lines in terms of the electrontemperatures of the emitting regions. We find that observations withimproved spectral resolution will be necessary in order that the lineratios become a useful tool for temperature determinations. Key words:solar transition region - sodium isoelectronic sequence - atomic data
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On the detection of binaries with a collapsed component.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&A....29..103S&db_key=AST
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Spectroscopic binaries with circular orbits.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971AJ.....76..544L&db_key=AST
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Spectroscopic Binaries and Collapsed Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969ApJ...156.1013T&db_key=AST
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INHABITED SKY
